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Dendrolycopodium
See list of 3 species in this genusIndividuals are sometimes found with conflicting character states (e.g., the phyllotaxy of one species on one branch and the phyllotaxy of another species on a different branch). These plants have been suspected to be of hybrid origin (Hickey 1978). This hypothesis is corroborated by intermediacy in trophophyll morphology and divergence angle. Given the close morphological similarity of New England’s three species, hybrids are rarely reported and likely undercollected.
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1a. Trophophylls of the upright shoot’s main axis 0.9–1 mm wide, widely ascending to spreading (i.e., diverging at an angle of 45–90 degrees), firm, prickly to the touch; trophophylls of the lateral branches arranged in 2 upper, 2 lower, and 2 lateral ranks [Fig. 8]
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1b. Trophophylls of the upright shoot’s main axis 0.5–0.7 mm wide, appressed to ascending (i.e., diverging at an angle of less than 30 degrees), pliable; trophophylls of the lateral branches arranged in 1 upper, 1 lower, and 4 lateral ranks [Figs. 9,10]
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2a. Lateral branches somewhat compressed; trophophylls of the lower rank of lateral branches shorter than those of the other ranks, those of the lateral ranks twisted, so that one surface faces up, the other surface faces down [Fig. 10]; trophophyll margins forming an angle of 27–59 degrees at the apex
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2b. Lateral branches terete; trophophylls of the lower rank of lateral branches similar in length to those of the other ranks, those of the lateral ranks not twisted, one surface facing the branch axis, the other surface facing outward [Fig. 9]; trophophyll margins forming an angle of 21–36 degrees at the apex
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Each photo represents one species in this genus.